Aircon Gas Top Up in Singapore - R22 & R410A Refill

How Refrigerant Keeps Your Aircon Cold

Cool Earth Aircon provides professional refrigerant gas top-up services across Singapore, from HDB flats in Tampines and Bedok to condos in Pasir Ris and landed homes in the east. Your aircon system relies on refrigerant gas to absorb heat from indoor air and release it outside. This gas circulates through a sealed loop of copper piping between the indoor evaporator coil and the outdoor condenser. When refrigerant levels drop below the correct amount, the system cannot transfer heat effectively, resulting in poor cooling performance or no cooling at all.

A gas top-up is one of the most common aircon servicing requests in Singapore, and for good reason - low refrigerant is among the top causes of aircon units that stop blowing cold air. However, it is important to understand that a gas top-up treats the symptom, not necessarily the cause. If your system is losing gas, there is usually a leak that needs attention.

Signs Your Aircon Is Low on Refrigerant

Whether you live in an HDB flat, condo, or landed property, these are the symptoms Singapore homeowners notice when refrigerant levels are low:

Reduced Cooling Power

The most obvious sign. Your aircon runs but the air coming out is not as cold as it should be. You might find yourself setting the temperature lower and lower, yet the room never feels comfortable. A properly charged system should produce supply air at 14°C to 18°C.

Ice Formation on Pipes

When refrigerant is low, the evaporator coil gets excessively cold in localised areas, causing moisture to freeze on the coil surface and the connecting pipes. If you see ice or frost on the copper piping coming out of your indoor unit, low gas is a very likely cause.

Constant Running Without Reaching Set Temperature

The compressor runs continuously because the system cannot achieve the thermostat set point. This not only fails to cool your home but also drives up electricity consumption and puts unnecessary strain on the compressor.

Unusual Sounds from the Outdoor Unit

A low-charge system can produce hissing or bubbling sounds at the outdoor unit. The compressor may also sound laboured or cycle on and off erratically.

Our Step-by-Step Gas Top-Up Process

As a trusted aircon service company in Singapore, our gas top-up procedure is systematic and thorough. We do not simply connect a cylinder and start filling - that approach leads to incorrect charging and potential compressor damage.

Pressure Measurement

The first step is connecting our calibrated manifold gauge set to the service valves on your outdoor unit. We measure both the high-pressure (discharge) and low-pressure (suction) sides and compare readings against the manufacturer’s specifications for your specific model. These readings tell us exactly how much refrigerant the system currently holds and how much needs to be added.

Leak Detection

If the gas level is significantly below specification, we inspect for leaks before topping up. Common leak points include:

• Flare joints - where copper pipes connect to the indoor and outdoor units
• Welded joints - solder joints along the piping run
• Evaporator coil - especially in older units where corrosion weakens the coil
• Service valves - at the outdoor unit connection points

Finding and repairing a leak before topping up ensures you are not wasting money on gas that will simply escape again. We use soap-bubble testing and electronic leak detectors to locate the source.

Precise Charging

We add refrigerant slowly and in controlled quantities, monitoring the gauge readings throughout the process. The goal is to reach the exact specified charge - not more, not less. Overcharging causes high head pressure, reduces efficiency, and can permanently damage the compressor. Undercharging means you will be back to the same problem within weeks. For brands like Daikin, Mitsubishi, and Panasonic, we follow the manufacturer’s exact charging specifications.

Performance Verification

After charging, we measure the supply air temperature from the indoor unit and compare it against expected values. We also check the temperature differential between return air and supply air. A healthy system should produce a differential of 8°C to 12°C.

R410A vs R32 vs R22 - Which Gas Does Your Unit Use?

Different aircon systems use different refrigerants. Using the wrong type causes serious damage.

R410A

The most common refrigerant in modern systems (manufactured after approximately 2010). R410A operates at higher pressure than R22 and requires equipment rated for these pressures. It does not deplete the ozone layer and is the current industry standard in Singapore.

R32

A newer refrigerant with lower global warming potential than R410A. Increasingly used in premium systems from Daikin, Panasonic, and Mitsubishi. R32 offers slightly better energy efficiency but requires trained handling as it is mildly flammable.

R22 (Being Phased Out)

Used in older systems manufactured before 2010. R22 is an ozone-depleting substance that is being phased out globally under the Montreal Protocol. As of 2026, supply is limited and prices have increased significantly. If your system uses R22, consider upgrading to a modern R410A or R32 system rather than continuing to invest in top-ups. Read our detailed comparison of R22 vs R410A aircon gas to understand the key differences.

When Topping Up Is Not the Right Fix

We believe in giving honest advice, even when it means recommending something other than what you initially called us for. In some cases, a gas top-up is not the right solution:

• Recurring low gas - If you have topped up within the past 6 months and the gas is low again, you have a leak that needs repair. Repeated top-ups are throwing money away.
• Dirty evaporator or fan coil - Poor cooling is not always a gas issue. A clogged fan coil can mimic low-gas symptoms. In these cases, an aircon chemical wash or full chemical overhaul is the proper fix.
• Very old systems on R22 - The cost of R22 gas plus repeated top-ups may exceed the value of upgrading to a new system with better efficiency and a manufacturer warranty.
• Compressor issues - If the compressor is struggling or making grinding noises, adding gas will not fix the underlying mechanical problem. We will advise you honestly after a full diagnosis.

How Cool Earth Compares

Get a Same-Day Diagnosis

Aircon not blowing cold? WhatsApp Cool Earth Aircon at +65 9427 3833 for a quick diagnosis. Our technician can usually determine over the phone whether a gas top-up is likely needed and schedule a same-day visit. We serve Tampines, Bedok, Simei, Pasir Ris, Sengkang, Hougang, and all areas across Singapore. Every gas top-up comes with our 90-day workmanship warranty, and we carry R410A, R32, and R22 refrigerant on our service vehicles for immediate charging.